Cubesats: Tiny Spacecraft, Huge Payoffs

These petite but powerful
satellites are spearheading a hands-on revolution around the world. And what
fist-sized CubeSats bring to space could mimic innovations sparked by the personal
computer here on Earth.

To look at them, you don't
see much ...and that's a good thing. No massive, expensive spacecraft that has
been years in the making and loaded to its sprawling solar panels with super-electronics
and other posh payload parts.

A standard CubeSat is a
motherboard of invention: About a 4-inch (10-centimeter) block of equipment
that tips the scale at roughly 2 pounds (1 kilogram). A handful are already
in space and with other launches planned for later this year.

Peep inside a CubeSat and
you'll spot off-the-shelf circuitry in the familiar form of microprocessors
and modem ports, and other microchip devices typically used in cell phones,
digital cameras and hand-held Global Positioning System (GPS) satellite navigation
units.

CubeSats will make be easier
and more cost effective to deploy into orbit.

Global congregation

The American Institute of
Aeronautics and Astronautics and Utah State University showcased the pint-sized
payloads at the 18th annual Conference on Small Satellites, held here last month.

The CubeSat initiative is
a global congregation of universities and private firms striving to advance
small satellite technology. Of the participating universities, more than 60
percent of CubeSat developers reside in the United States.

In June 2003, six CubeSats
were lobbed into orbit from Russia's Plesetsk launch site, executed by Eurockot
Launch Services GmbH of Bremen, Germany.

Later this year, if all
stays on track, over a dozen universities from around the world will take part
in hurling their CubeSats into space via a Dnper rocket. This launcher -- an
SS-18 missile sans warhead -- has been rehabilitated into a "ride for hire"
booster offered by ISC Kosmotras.

"When we started this,
I thought that it made sense for everybody to collaborate," said Robert Twiggs,
professor and consultant at Stanford University's Department of Aeronautics
and Astronautics and a pioneer in the rapidly growing world of small satellites.
"I'm very pleased that it's going the way it is."

Twiggs' main interest is
in the development, launch and operation of small, econo-class orbiters to do
feasibility demonstrations and to space-qualify new and novel components. He
is also spearheading the miniaturization of space experiments for low-cost satellite
missions.

Good things are coming

A CubeSat can be built for
under $25,000, although they typically come in at the $30,000 to $40,000 price
range - still a bargain. The "going-rate" per CubeSat launch is in
the $40,000 range.

There's already a CubeSat
Kit being offered that gives a builder a leg up on turning a space mission into
reality - and meeting a launch date "on time and under budget," says
one product brochure.

Regarding what services
CubeSats can perform, Twiggs said that he doesn't have the foggiest idea of
what the "killer application" of the little satellites will prove
to be. However, as for their utility, he's quick to respond.

"The utility to me
is to educate the students. The electronics are starting to get better...the efficiency
of solar cells is going up...and in a couple of years they're going to be very
capable little satellites. I think some good things are coming," Twiggs
told SPACE.com.

Commercial off-the-shelf

CubeSats aren't built with
special parts in huge NASA facilities.

"We use everything
we can get," Twiggs said. "If you've got lots of room to put everything in,
you end up not being too careful with it. That's the challenge. You've got to
really think hard when you're putting together a CubeSat."

The key to building small
is taking the "COTS" approach -- buying Commercial Off-The-Shelf.
"I think that's really the way to go," Twiggs advised. For a few tens
of dollars you can acquire capability that the "big guys" obtain at
mega-dollar prices.

Because the industry is
new, "we don't know how it has been done so we're less constrained by the established
way to solving the problem," said Michael Swartwout, assistant professor
of mechanical engineering at the School of Engineering and Applied Science at
Washington University in St. Louis, Missouri. "We can now finally play
to our strengths...our enthusiasm."

Freedom to fail

Universities have an inherent
advantage in developing "disruptive" space systems, Swartwout contends, and
that is the freedom to fail. In fact, he added, three of the six CubeSats placed
in orbit in 2003 were either never contacted or failed very early.

"Experimental failure
is a basic element of university life, and from the university's perspective,
a failed spacecraft is not necessarily a failed mission," Swartwout said.

Swartwout explained that
the tremendous reductions in the size and cost of electronics are making possible
"disposable" probes that function for only weeks, but whose very low
cost and short development cycle make their launch and operation affordable.

"Universities are uniquely
poised to take advantage of disposable spacecraft, and such spacecraft could
be used to develop 'disruptive' satellite technologies," he said.

California Polytechnic State
University (Cal Poly) in San Luis Obispo is a powerhouse in the CubeSat effort,
led by Cal Poly Aerospace Engineering Professor Jordi Puig-Suari.

In April, Cal Poly hosted
the first-ever CubeSat Developers' Workshop. That event brought together teams
in the United States and abroad to network and collectively shoulder ways to
reduce CubeSat costs and development time, and review how best to increase their
access to space and turn up the volume in terms of launch rate.

In addition to overseas
launches, CubeSat builders are looking to develop the capability of boosting
their satellites within the United States. A campaign is in progress with all
major launch providers to assess possibilities for the future.

Learn by building

Cal Poly is also home for
the CubeSat deployer, the P-POD. All universities involved in the CubeSat program
send their spacecraft to San Luis Obispo where Cal Poly students integrate each
into the P-POD and carry out testing before transporting them to the launch
site.

Things are extremely busy
at Cal Poly, said Spencer Studley, PolySat Project Manager and student. The
launch slated for later this year will include 14 CubeSats, he said, developed
by seven teams in the United States and four groups at international universities.

The CubeSats will be stuffed
within five P-PODs, each carrier device cocked and spring-loaded to deploy sets
of the tiny spacecraft.

"People are learning
as they are building," Studley said. "Between 40 to 50 universities
are actually in the process of building CubeSats."

Studley said that universities
are undertaking CubeSat work for multiple reasons: For their educational value
by enhancing student engineering skills, to carrying out science data gathering
or supporting a commercial space agenda.

According to Bryan Klofas,
Cal Poly student and coordinator for the university's Earth station: "There
are a lot of universities involved...and lots of far out ideas. You don't need
a lot of money to put a satellite in orbit. Smaller is better."

Twiggs at Stanford University
foresees a burgeoning role for CubeSats. Micro-thrusters could enable the spacecraft
to maneuver freely in Earth orbit. New radio and solar cell technology is within
reach, also making future CubeSats all the more productive.

"And look at the processors.
Every time they come out we get more computing power for less power consumption,"
Twiggs said. The same goes with the PDA, he said, the handheld personal digital
assistant.

"They are our saving
grace. They didn't know it but they're building stuff for us," Twiggs added.

Like the personal computer?

Big plans are afoot for
CubeSats. There is talk about flying tethers on the spacecraft, as well as toting
along inflatable packages - both techniques viewed as a way to hasten a CubeSat's
reentry and lessen worry about adding to already orbiting space clutter.

CubeSat innovators also
envision the small spacecraft deployed from the International Space Station
- chucked out of an airlock. Then there is the prospect of CubeSats toting biological
or hardware experiments that reenter and parachute to Earth.

"I hope the CubeSat
is like the personal computer...you don't know what the heck you're going to do
with this little box when you build it or what markets will be enabled. But
it's so cool, you've got to do it," Twiggs concluded.